A proximity-based wireless communication in use today employ inductive coupling between a resonant first coil antenna and a resonant second coil antenna. For smaller computing devices, a seamless interaction between these devices is becoming increasingly critical. Furthermore, since many of these computing devices are associated or in close proximity with a user's body (e.g., wristwatches, smartphones, smartcards, devices having tags, etc.), the user's body can play an important role in serving as a secure communication channel between the computing devices. This communication mode is typically referred to as human body communications (HBC) communication mode.
In traditional radiation-based communication modes such as radio frequency identifier (RFID), Bluetooth (BT), wireless fidelity (WiFi), Cellular, or the like, a communication from a transmitter to a receiver may occur over a distance of several meters and sometimes beyond line of sight. However, such radiation-based communication suffers from a key disadvantage, which is determining a user intent. In other words, it is substantially hard to determine which of the many devices that are within communication range need to be paired to enable communication. For example, in the RFID communication mode, some smartcards or devices with tags can be read from several meters away and beyond the line of sight of a reader. However, RFID techniques may suffer from bad selectivity. In other words, devices within the detection range is detected and a use of threshold is difficult to control. Furthermore, there is a limited transport security in a sense that all readers of a given proximity technology can read information from the devices with tags.
As such, there is a need for a design to enhance HBC communication mode to overcome at least these cited disadvantages.